What are pragmas and what are they good for?

C Interview Questions and Answers

(Continued from previous question...)

What are pragmas and what are they good for?

The #pragma directive provides a single, well-defined ``escape hatch'' which can be used for all sorts of (nonportable) implementation-specific controls and extensions: source listing control, structure packing, warning suppression (like lint's old /* NOTREACHED */ comments), etc.

(Continued on next question...)

Other Interview Questions

• What does the message warning macro replacement within a string literal mean?
• How am I supposed to know to allocate things?
• When should a type cast not be used?
• I am trying to declare a pointer and allocate some space for it
• How can f be used for both float and double arguments in printf? Aren't they different types?
• Someone explained to me that arrays were really just constant pointers.
• Does the sizeof operator work in preprocessor if directives?
• Suppose I want to write a function that takes a generic pointer ...
• What is the best style for code layout in C?
• Should I use symbolic names like TRUE and FALSE for Boolean constants, or plain 1 and 0?
• More...